Calculators & Converters
Our calculator tools handle everyday mathematical operations that students, professionals, and home users encounter regularly. Each calculator is built for speed and accuracy — just enter your numbers and get results instantly.
Percentage Calculator
Percentages appear everywhere: discounts, tips, tax rates, grade calculations, investment returns, and statistical data. Our Percentage Calculator handles three common scenarios: - Find what percentage one number is of another - Calculate the percentage increase or decrease between two values - Determine the result of applying a percentage to a number
Real-world examples: A shopper compares a 25% discount on a $120 jacket. The calculator shows $30 saved, final price $90. A student scores 85 out of 120 on an exam and wants their percentage: 70.8%. An investor sees their portfolio grow from $10,000 to $12,500: a 25% increase.
Fraction Calculator
Fractions are fundamental in mathematics, cooking, construction, and many trades. Our Fraction Calculator supports: - Addition, subtraction, multiplication, and division of fractions - Fraction simplification to lowest terms - Conversion between fractions and decimals - Support for mixed numbers and improper fractions
Example: A recipe calls for 2 1/2 cups of flour but you need to make half the recipe. Enter 2 1/2 ÷ 2 and get 1 1/4 cups. A carpenter has a 3/4 inch board and needs to subtract 5/16 inch: the result is 7/16 inch.
Random Number Generator
Random numbers are useful for games, statistical sampling, cryptography, simulations, and decision-making. Our generator offers: - Custom range (any minimum to maximum) - Integer or decimal output - Control over duplicates (allow or prevent) - Multiple results at once - Sort results for easy reading
Use cases: A teacher generates random student IDs for a lottery. A developer needs test data with specific value ranges. A gamer rolls virtual dice with custom parameters. A statistician creates a random sample from a population range.
All calculators work entirely in your browser. Your numbers stay private, results appear in real time, and there are no limits on how many calculations you can perform.
Related Utilities
- Percentage Calculator — Increase, Decrease, X of Y
Free percentage calculator: find a percentage increase, decrease, or X out of Y in seconds. 100% browser-based, no signup.
- Fraction Calculator — Simplify & Convert Fractions
Perform fraction arithmetic, simplify fractions, and convert between fractions and decimals. Free online fraction calculator tool.
- Random Number Generator — Pick Numbers Online
Generate random integers or decimals within a custom range. Control duplicates, sorting, and how many numbers to generate.
- Percentage Increase Calculator — Percent Change
Calculate the percentage increase or decrease between two values, or find the new value after a percent change. Free, instant and browser-based.
- X out of Y Calculator — Score to Percentage
Convert a score X out of Y into a percentage and an estimated letter grade instantly. Free, private, 100% browser-based calculator.
- Percentage Difference Calculator — Compare Values
Free percentage difference calculator: compare two values using their average, and see the percentage change between them side by side. Instant and private.
- Dice Roller — Roll D4 to D20 Dice Online
Roll one or many dice with 4, 6, 8, 10, 12 or 20 sides, or custom sides, and see each result plus the total. Includes a coin flip.
- Percent Off Calculator — Sale Price & Savings
Work out the sale price and amount saved from an original price and a percentage off, or reverse a discount to find the original price. Free and instant.
- Tip Calculator — Tip, Total & Split per Person
Free tip calculator: enter the bill, tip percentage and number of people to get the tip amount, total and per-person share. Optional tax rate.
- Random Picker — Pick Random Items From a List
Pick random items from a list online. Choose how many winners, avoid repeats, or remove each winner after the draw. Free, private and 100% browser-based.
- Margin Calculator — Gross Margin & Markup
Free margin calculator: enter cost and selling price to get gross margin, markup and profit, or find the price needed to hit a target margin.
- Percentage Error Calculator — Accuracy Check
Enter a measured and an accepted value to get the percent error, absolute error and signed deviation instantly, with the formula and worked examples.
- Random Team Generator — Balanced Random Teams
Split names into balanced random teams. Choose the number of teams or team size, add optional team names, and copy every team in one click. Free and private.